Question

Ey伙计们，我在将NSURL添加到数组并循环遍历时遇到了一些问题。以下是我的代码的相关部分：

RSS_ReaderAppDelegate.h：

@interface RSS_ReaderAppDelegate : NSObject <UIApplicationDelegate> {

    UIWindow *window;
    UINavigationController *navigationController;

    NSDictionary *RSSFeeds;
    NSMutableArray *RSSFeedURLs;
}

@property (nonatomic, retain) IBOutlet UIWindow *window;
@property (nonatomic, retain) IBOutlet UINavigationController *navigationController;

@property (nonatomic, retain) NSDictionary *RSSFeeds;
@property (nonatomic, retain) NSMutableArray *RSSFeedURLs;

RSS_ReaderAppDelegate.m：

@implementation RSS_ReaderAppDelegate

@synthesize window;
@synthesize navigationController;

@synthesize RSSFeeds, RSSFeedURLs;


#pragma mark -
#pragma mark Application lifecycle

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {    

    // Override point for customization after application launch.

    NSURL *url1 = [[NSURL alloc] initWithString:@"http://<some url>"]; //real URL has been hidden
    NSURL *url2 = [[NSURL alloc] initWithString:@"http://<some other url>"]; //real URL has been hidden

    [RSSFeedURLs initWithObjects: url1, url2, nil];

    [url1 release];
    [url2 release];

    for (NSURL *url in RSSFeedURLs) { //jumps right over this for loop
        NSXMLParser *xmlParser = [[NSXMLParser alloc] initWithContentsOfURL:url];
        XMLParser *parser = [[XMLParser alloc] init];
        [xmlParser setDelegate:parser];
        //Start parsing the XML file.
        BOOL success = [xmlParser parse];

        if(success)
            NSLog(@"No Errors");
        else
            NSLog(@"Error(s) encountered");
    }//for
    // Add the navigation controller's view to the window and display.
    [window addSubview:navigationController.view];
    [window makeKeyAndVisible];

    return YES;
}

所以[RSSFeedURLs initWithObjects: url1, url2, nil];似乎没有做任何事情，因为当我运行调试器并输入“po RSSFeedsURLs”它报告：“无法访问地址0x0处的内存”，因此永远不会输入for循环。我不知道为什么会这样，有人能为我解释这种情况吗？提前谢谢。

Answer 1

你想要：

RSSFeedURLs = [[NSMutableArray alloc] initWithObjects: url1, url2, nil];

但你应该想要：

rssFeedURLs = [[NSMutableArray alloc] initWithObjects: url1, url2, nil];

以大写字母开头的变量会导致很多混乱。

NSMutableArray initWithObjects不起作用

1 个答案: